DIY: 98 V70 Brake Hydraulic Overhaul (Hoses, Seals, Parking)

[xHeart]

Next step - brake bleeding. Would this MityVac vacuum instruction work since there isn't a 2nd person to assist.

MityVac Brake Bleeding

[xHeart]

Solo Method: Pump to above 15 inches of Mercury (in-Hg), opened the bleed value 1/2 turn - 180º. 30 seconds of air bubbles, then let it drip close to 2oz, each wheel, while keeping the reservoir filled close to Max marker.

using vacuum to bleed - Solo method

MVS_1005.jpg (837.07 KiB) Viewed 1924 times

[xHeart]

The test drive revealed sponginess, pedal travels to0 close to the floor at first application but it slow the the car, only second application stops the car with in a reasonable distance. Not safe for urban driving.

I will research a little this morning.

Looking closely with flashlight, fluid level, caliper piston, brake pads appear normal. ABS-Tracs worked since it was wet and slippery condition last night.

Would the 2-person method a good next step before the cylinder and booster relationship is explored?

[cn90]

Yes,

A 2-person bleeding method is much much better than Mightyvac (which works on vacuum principle).

Stop by a local mechanic shop and asks them to help. Tell them you already replaced the caliper, all you need is basic bleeding. Just turn the Respective front wheel OUTWARD (for RF wheel, turn the steering wheel all the way to the right) to expose the caliper, this way you don't even need to remove the tire.

This should be done in 10 minutes and the cost should be $10-$20.

Make sure the reservoir is full and drive slowly to the shop.

[abscate]

Thanks to all for self moderating and keeping it friendly.

I've got a pretty long track record of successfully bleeding cars singlehandedly just opening the bleeder valve and routing the bleed hose up about 12 inches above the caliper

Quick depression of the brake pedal, and a s....L.....o......w release forces air out and let's fluid be pulled from the reservoir instead of sucking air back in.

Road test and hard breaking test is MANDATORY if you do this.

[QuirkySwede]

It's pretty easy to recruit someone even if they know nothing about cars to help do a 2-person bleed job. Just be sure to get the commands and technique clear from the get go. 'Mechanic' calls out "Press" so 'driver' slowly presses the brake down (fast press can cause fluid to squirt out the master cylinder on some vehicles if you've left the cap off to monitor the fluid level easier) so other 'mechanic' can open valve. 'Driver' calls out "Down" to let Mech know travel limit is reached and valve should be closed. Mech calls "Release" after closing valve so the Driver knows they can let the pedal up without sucking air in. With some practice, just Down and Release are needed, and if both have a good feel of what's going on (like hearing the pedal travel and sensing brake fluid flow), it goes even faster.

If you're bleeding the front, might just as well do all four wheel starting with the farthest from the master (right rear, left rear, right front, left front), and use clear vinyl tubing so you can monitor the color, dirt, and or bubbles right as they come out the brake nipple. You can't see what's going on with opaque tubing and air will get in the drain side or get trapped in a pocket. Much clearer what's going on with clear tubing.

Make sure to replace the rubber brake nipple cap if missing, hard, dried out, or cracked, adding a smear of lube so it slips on/off so it can't glue in place. Makes the next brake flush easier.

Jreed has an excellent write up at Volvo 850 DIY: Front Flexible Brake Line Replacement with some great photos of brake hose cross-sections and dissections as well as damages that can occur.

[xHeart]

I got it right this time starting with passenger rear and ending at driver front. The rear valves turned without resistance after an hour on PB Blaster. The pedal is firm, it hold and resists pressure. The 2-person method is hands down ensuring and safest. Many thanks!

[xHeart]

Looking at my 12/28 post, the driver caliper hose connection was 1/4 turn over-twisted while fasteening the caliper to rotor, a small twist in the arch, Jason writes "no twist". Will the stress deteriorate the hose, the connection will not loosen b/c the stress would make it turn clockwise.

Do I need to correct this 1/4 turn over-rotatated hose, it is driver's caliper?

[cn90]

In an ideal world, yes, there should be no twist in the hose. However, knowing how difficult and trouble-some the connection between the metal pipe and the rubber hose, I'd tend to leave this alone if I were you.

On the other hand, if you recently replaced the rubber hose, then there should not be any seizing at the metal pipe/rubber hose junction. In this case, you should be able to loosen the connection and undo the twist in the rubber hose.

It is your call...

[xHeart]

In an ideal world, yes, there should be no twist in the hose. However, knowing how difficult and trouble-some the connection between the metal pipe and the rubber hose, I'd tend to leave this alone if I were you.

On the other hand, if you recently replaced the rubber hose, then there should not be any seizing at the metal pipe/rubber hose junction. In this case, you should be able to loosen the connection and undo the twist in the rubber hose.

It is your call...

The hoses are from 2008 brake job hence leaving it as is for now, but preparing for replacing pads, rotors, hoses, and likely rear reman-caliper by 2014 summer.

After a tons of snow, the ABS/Tracs got the job as well -- it is a Dr. MattyMoo variation. The pedal feels normal. A good start for 2014.